<template>
  <div id="home" class="wrapper">
    <nav-bar class="home-nav">
      <div slot="center">购物街</div>
    </nav-bar>
    <scroll class="content" ref="scroll" :probe-type="3" :pull-up-load="true" @scroll="contentScroll"
      @pullingUp="loadMore">
      <home-swiper :banners="banners" />
      <recommend-view :recommends="recommends" />
      <feature-view />
      <tab-control class="tab-control" :titles="['流行', '新款', '精选']" @tabClick="tabClick" ref="tab-control" />
      <good-list :goods="showGoods" />
    </scroll>
    <back-top @click.native="backClick" v-show="isShowBackTop" />
  </div>
</template>

<script>
  import HomeSwiper from "./childComps/HomeSwiper";
  import RecommendView from "./childComps/RecommendView";
  import FeatureView from "./childComps/FeatureView";

  import NavBar from "components/common/navbar/NavBar";
  import TabControl from "components/content/tabControl/TabControl";
  import GoodList from "components/content/goods/GoodsList";
  import Scroll from "components/common/scroll/Scroll";
  import BackTop from "components/content/backTop/BackTop";

  import {
    getHomeMultidata,
    getHomeGoods
  } from "network/home";

  export default {
    name: "Home",
    components: {
      HomeSwiper,
      RecommendView,
      FeatureView,
      NavBar,
      TabControl,
      GoodList,
      Scroll,
      BackTop
    },
    data() {
      return {
        banners: [],
        recommends: [],
        goods: {
          pop: {
            page: 0,
            list: []
          },
          new: {
            page: 0,
            list: []
          },
          sell: {
            page: 0,
            list: []
          }
        },
        currentType: "pop",
        isShowBackTop: false,
        isTabFixed: false,
        tabOffsetTop: 0,
        saveY: 0
      };
    },
    computed: {
      showGoods() {
        return this.goods[this.currentType].list;
      }
    },
    created() {
      // 1.请求多个数据
      this.getHomeMultidata();

      // 2.请求商品数据
      this.getHomeGoods("pop");
      this.getHomeGoods("new");
      this.getHomeGoods("sell");
    },
    mounted() {
      // 1.图片加载完成的事件监听
      const refresh = this.debounce(this.$refs.scroll.refresh, 50)
      // 调用事件总线中的方法
      this.$bus.$on('itemImageLoad', () => {
        refresh()
      })
    },
    methods: {
      /**
       * 事件监听相关的方法
       */
      debounce(func, delay) {
        let timer = null
        return function (...args) {
          if (timer) clearTimeout(timer)
          timer = setTimeout(() => {
            func.apply(this, args)
          }, delay)
        }
      },
      tabClick(index) {
        switch (index) {
          case 0:
            this.currentType = "pop";
            break;
          case 1:
            this.currentType = "new";
            break;
          case 2:
            this.currentType = "sell";
            break;
        }
      },
      contentScroll(position) {
        this.isShowBackTop = (-position.y) > 1000
        this.isTabFixed = (-position.y) > this.tabOffsetTop
      },
      backClick() {
        this.$refs.scroll.scrollTo(0, 0)
      },
      loadMore() {
        this.getHomeGoods(this.currentType)
      },
      /**
       * 网络请求相关的方法
       */
      getHomeMultidata() {
        getHomeMultidata().then(res => {
          // this.result = res;
          this.banners = res.data.banner.list;
          this.recommends = res.data.recommend.list;
        });
      },
      getHomeGoods(type) {
        const page = this.goods[type].page + 1;
        getHomeGoods(type, page).then(res => {
          this.goods[type].list.push(...res.data.list);
          this.goods[type].page += 1;

          this.$refs.scroll.finishPullUp();
        });
      }
    }
  };

</script>

<style scoped>
  #home {
    /* padding-top: 44px; */
    height: 100vh;
    position: relative;
  }

  .home-nav {
    background-color: var(--color-tint);
    color: #fff;

    position: fixed;
    left: 0;
    right: 0;
    top: 0;
    z-index: 9;
  }

  .tab-control {
    position: sticky;
    top: 44px;
    z-index: 9;
  }

  .content {
    overflow: hidden;

    position: absolute;
    top: 44px;
    bottom: 49px;
    left: 0;
    right: 0;
  }

  /*.content {*/
  /*height: calc(100% - 93px);*/
  /*overflow: hidden;*/
  /*margin-top: 44px;*/
  /*}*/

</style>
